In the past, chewing gums in the form of shaped centers or cores, e.g. pellet gums, have been coated both with sugar and sugarless coatings to produce a candy-like, crunchy outer taste in the mouth with a chewable gum center portion. Conventionally, the core is a soft chewing gum portion, whereas the coating is crunchy or hard. In the case of sugarless coatings, aqueous solutions of xylitol, mannitol, maltitol and sorbitol, known as syrups, have been primarily employed. Such syrups may contain additives such as moisture absorbing compounds, anti-adherent compounds, dispersing agents, film-forming agents, binders and the like.
U.S. Pat. No. 4,127,677 to Fronczkowski et al., issued Nov. 28, 1978, discloses a xylitol-coated chewing gum. The coating is applied via a coating syrup containing from about 55% to 70% solids of which from about 95% to about 99.5% is xylitol. The solids also include about 0.5% to about 1.5% of colorant (e.g., titanium dioxide), and about 0.5% to about 1.5% binder and/or suspending agent (e.g., gum arabic). In the Example Section (Column 4) it is disclosed that the gum centers to be coated are placed in a standard revolving coating pan. The gum pieces are dedusted using cool dry air and the xylitol-coating solution is sprayed thereon until the desired weight or gauge is reached. The coated gum pieces are jogged or tray dried and then polished, by conventional means.
U.S. Pat. No. 4,105,801 to Degliotti, issued Aug. 8, 1978, discloses a dragee comprising a core and shell of edible material enveloping the core and adhering to the latter. The shell is formed by an intimate mixture of microcrystals of xylitol with a normally solid fatty substance selected from the group consisting of mono-,di- and triglyceride of palmitic-, stearic-, and oleic acids and cocoa butter. The proportions of fatty substance to xylitol is 0.5 to 15 parts by weight of fatty substance to each 100 parts by weight xylitol. This patent also discloses a process for preparing a dragee described above. The process is characterized in that a batch of the cores for the dragees is submitted to coating with the use of an aqueous concentrated xylitol solution having dispersed therein the fatty substance. The solution is sprayed over the batch at a temperature at which said fatty substance is in its molten or superfused state while the batch is tumbled and maintained at a temperature lower than, or at the utmost equal to, the melting point of the fatty substance.
U.S. Pat. No. 4,238,510 to Cherukuri et al., issued Dec. 9, 1980, discloses a sugarless coated comestible whose coating comprises a sweet material in crystalline form. The coating consisted essentially of sorbitol alone or in admixture, mannitol, and/or hydrogenated starch hydrolysate. The sorbitol is disclosed as being present in an amount within the range of from about 45% to about 90% by weight of the coating. Also disclosed is a method for applying the sugarless coating to centers. The method includes the steps of applying to the centers a first coating syrup which contains a sweetener such as sorbitol and/or other non-sugar sweetener, for example, mannitol or hydrogenated starch hydrolysate, an adhesion or binder component and a film-forming component, to thereby coat the centers with the first coating syrup, then a dusting mix is applied to the centers coated with the first coating syrup. The dusting mix includes one or more sweeteners, such as employed in the first coating syrup, in powdered form, and a moisture absorbing component, an anti-sticking component and a dispersing agent. It is disclosed that if desired a second coating syrup may be applied to smooth out the coating of the centers and provide a shine thereto. The second coating generally includes ingredients similar to that present in the dusting mix but dispersed in water.
U.S. Pat. No. 4,317,838 to Cherukuri et al., issued Mar. 2, 1982, discloses a method for forming a sugarless coating on centers of chewing gum or other comestibles which includes the steps of applying to the centers a coating syrup which contains a sweetener such as sorbitol and/or other non-sugar sweetener, an adhesion or binder component such as gum arabic and a film forming component, an anti-adherent or filler component, and a dispersing agent to thereby coat the centers with the coating syrup. A dusting mix including one or more sweeteners, such as employed in the coating syrup, in powdered form, and a moisture absorbing component, an anti-adherent component and a dispersing agent are also employed.
The problems associated with forming a sugarless e.g., xylitol) coating on comestibles, e.g. chewing gum, have been many. These problems include chipping, flaking, and cracking of the coating upon the attainment of the desired coating thickness, mottling of the coating, poor texture (such as a rough surface), and lack of crunchiness upon the initial chewing of the comestible. Without wishing to be bound by theory, it is believed that some of these problems may be due to inflexibility of the coating in response to the geometric shape of the comestible being coated, a deficiency in the film-forming properties of the coating, and a lack of uniformity in the crystallization of the sweetener throughout the coating.
Another problem associated with coating comestibles, such as pharmaceuticals, chewing gums, and confectioneries, are the long coating times, e.g., several hours, needed to produce a coated product. The inherently hydroscopic nature alone of some of the sugarless sweeteners usually used (e.g., xylitol, sorbitol, glycerol, and the like) creates problems in producing a finished coating that is substantially resistant to moisture absorption. Such protection from moisture is of further concern where a moisture sensitive artificial sweetener, such as for example aspartame, is to be used in the coating. The use of such sugarless sweeteners in a process involving long coating times would result in even more difficulties in obtaining a sugarless coating substantially resistant to moisture absorption. Moisture absorption by a sugarless coating could effect the coatings smoothness and hardness in an adverse way as well as substantially reducing or eliminating completely the crunchiness of the coating.
In addition, another problem, in view of present interests in both sugar and sugarless coatings, is the need to use different processes for applying the two different types of coatings. Thus, at present, if it is desired to change from applying a sugarless coating to applying a sugar coating (or visa versa) it is necessary to change the process.
Therefore, in view of the foregoing, a sugarless coated product whose coating has a good appearance, good texture, good flexibility relative to the shape of the comestible being coated, and good film-forming properties--i.e., a coating which is smooth, hard and crunchy--would be a welcome contribution to the art. In addition, a process for producing either a sugarless or a sugar coated comestible having the desired properties set forth hereinbefore (i.e., a coating which is smooth, hard and crunchy) would also be a welcome contribution to the art. Such contributions are provided by this invention.